I live in Salt Lake City and moved into a house with large out of control grape vines. There is a trellis of sorts that is about 6 feet tall and about 30-40 feet long and 3 feet wide. There appear to be two plants that have grown (according to the neighbors) for over 25 years. I do not know what kind of grapes they are. They do not really bear fruit, but what the bear when they try are small green grapes that mildew and brown before ripe. The base of the two plants are easily 6 inches across and there are long and unsupported branches that have been growing for years and years. They have grown over the wire link fence and around and up and hang loose and basically are out of control. Mostly there is a huge abundance of foliage. Last year we pruned them back to what seemed to be the oldest 'limbs' but those are still about 1-2 inches thick and hanging kind of loose. This has 'forced' growth to come out of the older parts of the base plant. The foliage is basically out of control. It grows up and out and shoots skyward. I have tied/wired some of the growth along the trellis. I have no idea what I am doing and when I try to research about this, I can't really find how to get an untended vine (20+ years untended) back in control Any help is very appreciated.
